Lowcost capable CNC - Make vs Buy?

[Doddy]

As of 9:30 - I guess your spreadsheet will be live and therefore subject to change as you respond to comments?

I note the comment re. suppliers, but buying from China - usually the best option - figure on getting stung for import duty especially for big/heavy/shiny items like these.

Those particular stepper drivers need DC so, depending on the transformer selection you might be cutting it fine (by £20 or so) for the rectifier & caps. Unless you've found a suitable toroidal transformer for £50. Hmmm, 36V?, and those stepper drivers?, you'll be compromising the potential performance - but that's a different question to the one you've asked here.

You've completely over-egged your CY cable costs - but that's no bad thing. You can cover the costs of all cabinet wiring and marking with the budget you have.

Oh, What about a cabinet to hold the control gear (+£75)? E-Stop ("oh shit!") button, miscellaneous switches, relays and bases, add £100 (or take that off your budget for the PC). Connectors etc, into the cabinet - add another £60, unless you're hard-wiring everything (I'd not recommend this option!).

You'll need a 24V and 5V supply also. Think if you're using DIN rail and terminals in the cabinet.

[JAZZCNC]

Ok well, your high in some areas and missing stuff in others but it will all balance out to be around that figure if you shop a little better.
Though be honest prices are changing all the time with the world being in meltdown so I'm going to revise my estimate and say £2500 might be a more realisitc figure with the spec your at now by the time it's finished.
However you'll have a machine that is worth double that amount and will blow the likes of I2R, Felder, Axiom out the water.

PC cost is way to high, £75 will get you a PC to run this no problem.

Aluminium can be sourced cheaper is you try local metal suppliers. I pay roughly 30% less than Ali warehouse ask, then you save carriage on top if you collect.
If you have any local engineering place it's worth calling in and asking about there Scrap bins, sometimes they what they call little pieces of scrap we call gantry sides.!

Just little things and savings like this all add up. 5 for less than your 3.

https://www.ebay.co.uk/itm/5x-Induct....c100010.m2109

Now you have gone with the Uc400 but this means you'll need a breakout board which you haven't accounted for. This is why I mentioned the AXBB rather than uc300 or 400. It saves you money and as everything you need.

The drives you stated like Doddy says are 50Vdc max so you can't use a 36V toroidal as you'll blow them up. Remember the 10% safety margin.
This is another reason why it's worth paying an extra $20 for the bigger drives/motors. You also don't need the Capacitors and bridge rectifier so your costs for PSU are just the toroidal transformer.

Regards customs and buying from China. Try to buy everything from same place, for instance, Fred at BST can supply everything but the drives/motors, as it will save you money on shipping.
I would build the Z-axis my self as it would be cheaper and better.

Customs will charge VAT on the (**)invoice amount declared(**), there will also be an admin fee of around £15-20 from the shipping agent.
Ask the supplier to keep the (**) low.

With a little careful buying, you'll get the costs down more but you have missed a few reasonably pricey things, like an electrical cabinet but like I say it will probably balance out with things you have overpriced.